Rheostat for an electrical battery indicator



July 26, 1938. B. H. CAMPBELL RHEOSTAT FOR AN ELECTRICAL BATTERY INDICATOR Filed Nov. 18, 1956 INVENTOR ATTORNEYS Patented July 26, 1.938 i 2.123%

UNITED STATES PATENT OFFICE RHEOSTAT FOR AN ELECTRICAL BATTERY INDICATOR Bruce H. Campbell, Atlanta, Ga.

Application November 18, 1936, Serial No. 111,551

ll Claim. (fill. 2011-62) This invention relates to a rheostat for an elecelectric circuit I is connected to terminals of the trical battery indicator and has for the primary battery l, as shown in Figure 3, and to the reobject the provision of a device of this character sistance coil l2 and the contact rod l3. The which may be readily connected in an electric circuit l5 includesa switch l5 and is also con- 5 circuit of an indicatorand adapted for actuation nected to a meter H. The meter is of the con- 6 by the specific gravity of the fluid of a storage ventional construction for the purpose of indibattery to bring about operation of the indicator eating the charge in the battery. The face or to permit a person to easily ascertain the apdial of the meter may have any suitable graduaproximate electrical charge of said battery. tions thereon or divided, as shown in Figu e 10 With these and other objects in view, this into blocks titled high, medium, low and 10 invention consists in certain novel features of low water. The indicating hand of the meter construction, combination and arrangement of moves over the blocks, according to the charge of parts to be hereinafter more fully described and the battery. The float 6 rises and falls in acclaimed. cordance with the specific gravity of the fluid For a complete understanding of my invention, or electrolyte of the battery and the float and 15 reference is to be had to the following description cat whiskers thereof moving relative to the reahd accompanying drawing, in which sistance coil varies the positions of the indicator Figure 1 is a fragmentary vertical sectional hand of the meter over the face of the latter so view illustrating my invention applied to a, batthat the operator, pilot or driver can readily asten, certain the charge in the battery. The switch I6 20 Figure 2 is a sectional view taken on the line controls the electrical circuit. 2-2 of Figure 1. Having described the invention, I claim:

Figure 3 is a fragmentary perspective view 11- A rheostat for battery indicators comprising lustrating an electrical connection between my a supporting partition of insulating material, a invention and the battery. contact rod secured to and depending from said 25 Referring in detail to the drawing, the nupartition and including a terminal e te d n meral l indicates a storage battery and to adapt above said partition for connection in an elecmy invention to the battery, the casing 2 thereof tric circuit of an indicator, a resistance coil is provided with a port 3 and secured to the cassecured to and depending from the partition and ing is a float chamber 4 provided with a port 5 paralleling and. spaced from the contact rod and 30 aligning with the port 3 so that the fluid of the nclud g a te a the pp end d battery may seek its level within the float chamranged above the partition for connection in the her. A float 5 operates in the float chamber and electric circuit, a second partition of insulating has its movement guided by a partition I sepmaterial connecting the lower ends of the conarating the float chamber into a fluid comparttact rod and the resistance coil and cooperating 3| ment 8 and a compartment 9 to receive elecwith the first partition in maintaining the contrical appliances. The chamber 9 is closed by tact rod and resistance coil in spaced relation and a removable cap l0 and has located therein a parprovided with an opening between said contact tition I I. The partitions I and H support in rod and the resistance coil, a float stem'slidable 4.0 spaced relation an electrical resistance coil l2 in said opening, a float for said stem, and a plu- 40 and a contact rod IS. The stem or rod of the rality of flexible contact elements extending float 6 operates between the resistance coil and through the stem and carried thereby for engagethe contact rod and has secured thereto cat ment with the contact rod and the resistance coil. whiskers I! which have wiping engagement with the resistance coil l2 and the contact rod l3. An BRUCE H. CAMPBELL. I w 

